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  • 4pt vs 7pt 7

    From Timothy Chow@21:1/5 to All on Sun Jun 18 09:30:18 2023
    This is the last one in this series. I have plenty more, but I
    figured that a week's worth of problems on a single theme is plenty.
    If there is interest, I could post another 7 problems on the same
    theme, maybe next month.

    XGID=-a---BC-CAaAcC---c-e--b-B-:0:0:1:42:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O X |
    | X O | | O O X |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | O X | | X |
    | O X | | X X |
    | O X O X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 159 O: 138 X-O: 0-0
    Cube: 1
    X to play 42

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sun Jun 18 11:06:12 2023
    On 6/18/2023 9:30 AM, Timothy Chow wrote:
    This is the last one in this series.  I have plenty more, but I
    figured that a week's worth of problems on a single theme is plenty.
    If there is interest, I could post another 7 problems on the same
    theme, maybe next month.

    XGID=-a---BC-CAaAcC---c-e--b-B-:0:0:1:42:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     | X           O    |   | O        O     X |
     | X           O    |   | O        O     X |
     | X           O    |   | O                |
     |                  |   | O                |
     |                  |   | O                |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     | O           X    |   | X                |
     | O           X    |   | X  X             |
     | O  X  O  X  X    |   | X  X           O |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 159  O: 138 X-O: 0-0
    Cube: 1
    X to play 42


    Clearly I need to see more of these so another batch would be welcome.

    I like the aphorism "attack with the four point, prime with the bar
    point" and if you ask "what is the game plan" and answer correctly it
    might lead to the correct answer to these 4 vs 7 point choices.

    "attack a single checker, prime two" is an often incorrect saying (and
    often correct too) that would favor the attacking play, i.e. making the
    four point in case we get a shot next roll. But making the four point
    leaves 13 shots while the bar point leaves none while making a solid
    four prime. So, I'll make the bar.


    --
    Ah....Clem
    The future is fun, the future is fair.

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  • From Timothy Chow@21:1/5 to All on Tue Jun 20 09:07:43 2023
    XGID=-a---BC-CAaAcC---c-e--b-B-:0:0:1:42:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O X |
    | X O | | O O X |
    | X O | | O |
    | | | O |
    | | | O |
    | |BAR| |
    | | | |
    | | | |
    | O X | | X |
    | O X | | X X |
    | O X O X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 159 O: 138 X-O: 0-0
    Cube: 1
    X to play 42

    This is another example where strategic considerations point toward
    making the 4pt, and those considerations override cleaning up a blot.

    1. Rollout¹ 8/4 6/4 eq:+0.239
    Player: 56.51% (G:15.85% B:0.64%)
    Opponent: 43.49% (G:13.57% B:1.04%)
    Confidence: ±0.014 (+0.225..+0.253) - [100.0%]

    2. Rollout¹ 11/7 9/7 eq:+0.150 (-0.089)
    Player: 54.39% (G:15.18% B:0.65%)
    Opponent: 45.61% (G:14.19% B:0.81%)
    Confidence: ±0.013 (+0.138..+0.163) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
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